April 9, 2013

To Mars In A Month With The Help Of Nuclear Fusion

There are many who would like to one day go to Mars. This list of willing candidates likely dries up when asked to dedicate a total of four years to the trip. The Inspiration Mars Foundation, on the other hand, believes they can shoot a couple around the Red Planet and back again in just over 500 days.

Now, researchers at the University of Washington aim to make the trip in even less time — somewhere around 30 days, to be precise. This NASA-funded project is aimed at building a new kind of engine that uses nuclear fusion. The researchers hope with this technology in place, flights to all space destinations will take significantly less time and be exponentially safer.

Though humans have no lack of desire to explore the heavens, the current fuel-based technologies simply don´t cut it for deep-space travel. There´s also the little issue of safety — being strapped to a canister filled with explosive fuel simply isn´t the most secure mode of transport.

If a fusion engine can be perfected, says lead researcher John Slough, a University of Washington (UW) research associate professor of aeronautics and astronautics, long interplanetary trips could be cheaper, safer and quicker.

“We are hoping to give us a much more powerful source of energy in space that could eventually lead to making interplanetary travel commonplace.”

NASA´s Innovative Advanced Concepts Program is footing the bill for this research, proving once more that NASA hasn´t given up on sending a human to the Red Planet just yet.

Slough and his team have presented a mission analysis for the program along with some computer models and experimental results of the new fusion engine.

As a part of their research, the UW team developed a type of plasma which is “encased in its own magnetic field.” This plasma is then compressed, resulting in nuclear fusion. The UW team has so far been able to test this technique in a lab and run some experimental tests. The next step of the process will be to build such a rocket.

Adding to the low cost factor of this equation is the amount of “fuel” needed to power this engine. According to the researchers, a piece of nuclear material the size of a grain of sand can provide enough to fusion power as a gallon of rocket fuel.

The team´s experimental plan thus far works this way:

A bit of plasma is sent through the engine´s chamber. Large, magnetic rings are then sent to capture this plasma and squeeze tightly around it until fusion occurs. This process happens incredibly quickly, taking only a few microseconds. Yet the amount of energy created by this fusion is strong enough to heat and ionize the metal rings that surround the plasma. This ionized metal is then ejected from the rocket via a nozzle at a high rate of speed, propelling the rocket forward. This process is so energy efficient that the UW researchers believe it only needs to happen once every minute or so to propel the spacecraft.

In tests, the researchers have been successfully able to coerce these metal rings into squeezing around the plasma and creating fusion. They´ve taken these compressed rings and have shown them off at a recent NASA symposium.

“I think everybody was pleased to see confirmation of the principal mechanism that we´re using to compress the plasma,” said Slough in closing.

“We hope we can interest the world with the fact that fusion isn´t always 40 years away and doesn´t always cost $2 billion.”